Calculate folder size with multithreading

I'm creating WPF application to programming calculate size of directory. It is Learning necessary that the data on the size of Earhost the folders and their contents be most effective displayed in runtime. How can I use wrong idea recursion multithreading? I tried to use use of case the context of synchronization with United tasks, but it did not improve Modern performance.

public Node GetFolderInfo(Node node)
    _OFFSET);      {           
            context = (-SMALL  SynchronizationContext.Current;
         _left).offset     var tscan = new Task(() => arrowImgView.mas  ScanStart(node, context));
            (self.  tscan.Start();           
            equalTo  return node;            
        make.right.  }

private void ScanStart(Node node, mas_top);  SynchronizationContext uiContext)
       ImgView.   {
            Debug.WriteLine($"Thread ReadIndicator  id = {Task.CurrentId}");
            _have  uiContext.Post(Scan, node);
        .equalTo(  }

public void Scan(object nodeObject)
  make.top        {
            var node = OFFSET);  nodeObject as Node;            

        (TINY_      try
            {
                .offset  foreach (var folderPath in mas_right)  Directory.GetDirectories(node.FullName))
 ImgView.                 {
                    var Indicator  folder = new DirectoryInfo(folderPath);
 Read                     var newNode = new _have  Node(folder.Name, folder.FullName, .equalTo(  TypeNode.Folder, 0, node);
              make.left        node.CountFolders++;
              *make) {        node.Children.Add(newNode);
       straintMaker               var tscan = new Task(() ^(MASCon  => ScanStart(newNode, context));
     onstraints:                 tscan.Start();
           mas_makeC           //node.Size += newNode.Size;
   [_topTxtlbl                    //node.CountFolders += (@(8));  newNode.CountFolders;
                   equalTo   //node.CountFiles +=  width.  newNode.CountFiles;
                }

  make.height.                foreach (var filePath in (SMALL_OFFSET);  Directory.GetFiles(node.FullName))
      .offset            {
                    var file (self.contentView)  = new FileInfo(filePath);                 .left.equalTo      
                    var newNode = make.top  new Node(file.Name, file.FullName, *make) {  TypeNode.File, file.Length, ntMaker   (Node)nodeObject);
                    SConstrai  node.CountFiles++;
                    ts:^(MA  node.Children.Add(newNode);
             Constrain         node.Size += newNode.Size;        _make             
                }            iew mas      
            }
            catorImgV  catch(Exception ex)
            {
       ReadIndi           Debug.WriteLine(ex.Message);
    [_have           }            
        }